The Illinois Environmental Protection Agency declared an Air Pollution Action Day today in the Chicago Metropolitan area due to elevated particle pollution caused by Canadian wildfire smoke.

Here’s what you should know about best practices and who’s likely to be most affected.

What is an Action Day?

Action Days are typically called when the air quality index, also known as the AQI, gets into unhealthy ranges, according to the U.S. AQI website.

In Illinois, an Air Pollution Action Day is issued when the air quality is forecast to be at or above the Orange category for two or more consecutive days, meaning the air is unhealthy for sensitive groups.

The Illinois EPA said in a news release that wildfire smoke would likely continue to have an impact on particulate levels in the northern third of Illinois, with Orange AQI levels on June 4th and June 5th, posing a potential health hazard to sensitive populations. Surface smoke may also have impacts further south in areas with a Moderate/Yellow forecast.

Where is Action Day being issued?

The Action Day includes the counties of Cook, DuPage, Kane, Kendall, Grundy, Lake, McHenry and Will, according to the Illinois EPA.

What should you do on Action Days?

The EPA recommends businesses and residents take part in the following activities to reduce air pollution:

•  Limit Driving – combine errands, walk, or bike if possible.
• If driving, avoid idling, consolidate errands and keep your vehicle and other engines properly tuned.
• Conserve energy to reduce energy demands.
• Use environmentally friendly household and cleaning products.
• Avoid using gasoline-powered equipment like lawnmowers and leaf blowers.
• Notify colleagues, friends and family to help protect their health and encourage actions.

Who is most at risk?

Those most at risk due to air pollution are individuals with respiratory or pulmonary disorders, as well as children and adults who are active outdoors.

People in these groups should follow their doctor’s advice and look out for symptoms like wheezing, coughing, a fast heartbeat, fatigue, chest pain and shortness of breath. If symptoms worsen, you should call your physician or 911.

AQI scale explained

Here’s a breakdown of the EPA’s AQI scale for those who are unaware:

• Good (0 to 50): Air quality is satisfactory, and air pollution poses little or no risk.
• Moderate (51 to 100): Air quality is acceptable. However, there may be a risk for some people, particularly those who are unusually sensitive to air pollution.
• Unhealthy for Sensitive Groups (101 to 150): Members of sensitive groups may experience health effects. The general public is less likely to be affected.
• Unhealthy (151 to 200): Some members of the general public may experience health effects; members of sensitive groups may experience more serious health effects.
• Very Unhealthy (201 to 300): Health alert. The risk of health effects is increased for everyone.
• Hazardous (301 and higher): Health warning of emergency conditions. Everyone is more likely to be affected.

Air quality map